From patchwork Tue Jun 20 10:34:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steffen Klassert X-Patchwork-Id: 13285594 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D51C310781 for ; Tue, 20 Jun 2023 10:35:19 +0000 (UTC) Received: from a.mx.secunet.com (a.mx.secunet.com [62.96.220.36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8E5E1B6 for ; Tue, 20 Jun 2023 03:35:16 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by a.mx.secunet.com (Postfix) with ESMTP id 5290B207B3; Tue, 20 Jun 2023 12:35:15 +0200 (CEST) X-Virus-Scanned: by secunet Received: from a.mx.secunet.com ([127.0.0.1]) by localhost (a.mx.secunet.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id emPOJFM1_byP; Tue, 20 Jun 2023 12:35:14 +0200 (CEST) Received: from mailout2.secunet.com (mailout2.secunet.com [62.96.220.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by a.mx.secunet.com (Postfix) with ESMTPS id 72A73207C6; Tue, 20 Jun 2023 12:35:14 +0200 (CEST) Received: from cas-essen-01.secunet.de (unknown [10.53.40.201]) by mailout2.secunet.com (Postfix) with ESMTP id 63EEA80004A; Tue, 20 Jun 2023 12:35:14 +0200 (CEST) Received: from mbx-essen-01.secunet.de (10.53.40.197) by cas-essen-01.secunet.de (10.53.40.201) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Tue, 20 Jun 2023 12:35:14 +0200 Received: from gauss2.secunet.de (10.182.7.193) by mbx-essen-01.secunet.de (10.53.40.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Tue, 20 Jun 2023 12:35:13 +0200 Received: by gauss2.secunet.de (Postfix, from userid 1000) id 5496631801D6; Tue, 20 Jun 2023 12:35:13 +0200 (CEST) From: Steffen Klassert To: David Miller , Jakub Kicinski CC: Herbert Xu , Steffen Klassert , Subject: [PATCH 1/6] xfrm: Treat already-verified secpath entries as optional Date: Tue, 20 Jun 2023 12:34:25 +0200 Message-ID: <20230620103430.1975055-2-steffen.klassert@secunet.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230620103430.1975055-1-steffen.klassert@secunet.com> References: <20230620103430.1975055-1-steffen.klassert@secunet.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: cas-essen-01.secunet.de (10.53.40.201) To mbx-essen-01.secunet.de (10.53.40.197) X-EXCLAIMER-MD-CONFIG: 2c86f778-e09b-4440-8b15-867914633a10 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,SPF_HELO_NONE, SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org From: Benedict Wong This change allows inbound traffic through nested IPsec tunnels to successfully match policies and templates, while retaining the secpath stack trace as necessary for netfilter policies. Specifically, this patch marks secpath entries that have already matched against a relevant policy as having been verified, allowing it to be treated as optional and skipped after a tunnel decapsulation (during which the src/dst/proto/etc may have changed, and the correct policy chain no long be resolvable). This approach is taken as opposed to the iteration in b0355dbbf13c, where the secpath was cleared, since that breaks subsequent validations that rely on the existence of the secpath entries (netfilter policies, or transport-in-tunnel mode, where policies remain resolvable). Fixes: b0355dbbf13c ("Fix XFRM-I support for nested ESP tunnels") Test: Tested against Android Kernel Unit Tests Test: Tested against Android CTS Signed-off-by: Benedict Wong Signed-off-by: Steffen Klassert --- include/net/xfrm.h | 1 + net/xfrm/xfrm_input.c | 1 + net/xfrm/xfrm_policy.c | 12 ++++++++++++ 3 files changed, 14 insertions(+) diff --git a/include/net/xfrm.h b/include/net/xfrm.h index 33ee3f5936e6..151ca95dd08d 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1054,6 +1054,7 @@ struct xfrm_offload { struct sec_path { int len; int olen; + int verified_cnt; struct xfrm_state *xvec[XFRM_MAX_DEPTH]; struct xfrm_offload ovec[XFRM_MAX_OFFLOAD_DEPTH]; diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c index 39fb91ff23d9..b731687b5f3e 100644 --- a/net/xfrm/xfrm_input.c +++ b/net/xfrm/xfrm_input.c @@ -131,6 +131,7 @@ struct sec_path *secpath_set(struct sk_buff *skb) memset(sp->ovec, 0, sizeof(sp->ovec)); sp->olen = 0; sp->len = 0; + sp->verified_cnt = 0; return sp; } diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 6d15788b5123..ff58ce6c030c 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -3349,6 +3349,13 @@ xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int star if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id)) return ++idx; if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { + if (idx < sp->verified_cnt) { + /* Secpath entry previously verified, consider optional and + * continue searching + */ + continue; + } + if (start == -1) start = -2-idx; break; @@ -3723,6 +3730,9 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, * Order is _important_. Later we will implement * some barriers, but at the moment barriers * are implied between each two transformations. + * Upon success, marks secpath entries as having been + * verified to allow them to be skipped in future policy + * checks (e.g. nested tunnels). */ for (i = xfrm_nr-1, k = 0; i >= 0; i--) { k = xfrm_policy_ok(tpp[i], sp, k, family, if_id); @@ -3741,6 +3751,8 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, } xfrm_pols_put(pols, npols); + sp->verified_cnt = k; + return 1; } XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);